<template>
  <div>
    <div v-show="isShow">全场清仓，全部5折</div>

    <ul>
      <li v-for="item in goods" :key="item.name">
        <div>{{ item.name }}</div>
        <div>{{ item.price }}</div>
        <div>折扣：{{ discountDefault }}</div>
      </li>
    </ul>

    <input type="text" v-model="discountDefault" />

    <h4>总价:{{ total }}</h4>

    <button @click="sale">点击开启促销活动</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      goods: [
        {
          name: 'mac电脑',
          price: 15000,
        },
        {
          name: '百事可乐',
          price: 3,
        },
        {
          name: '保温杯',
          price: 99,
        },
        {
          name: '保暖手套',
          price: 130,
        },
      ],
      isShow: false,
      discountDefault: 0.5,
    }
  },

  methods: {
    sale() {
      this.isShow = true

      this.goods.forEach(
        (item) => (item.price = item.price * this.discountDefault)
      )
    },
  },

  computed: {
    total() {
      return this.goods.reduce((prev, item) => item.price + prev, 0)
    },
  },
}
</script>

<style scoped>
ul {
  margin: 0;
  padding: 0;
}

li {
  list-style: none;
  width: 200px;
  height: 80px;
  padding: 10px 0 0 0;
  border: 2px solid #333;
}
</style>
